Infusion systems for the infusion of liquid therapeutic products into the human or animal body are known in the art, e.g. from U.S. Pat. No. 4,395,259. Such systems are particularly, though not exclusively, intended for the infusion of insulin into the body for diabetes therapy. The system has an infusion device which may be implanted or worn externally on the body, and a remote controller that can wirelessly monitor the function of the infusion device. The infusion device includes a pump, a reservoir of the therapeutic product, control electronics and a battery power supply.
Such devices tend to be relatively large in size and have a high electrical power requirement necessitating frequent replacement or recharging of the battery. Extended or frequent periods where a user cannot receive delivery of the therapeutic product due to refilling or replacement of the reservoir of therapeutic product, or replacement or recharging of the battery are undesirable from a medical standpoint and are inconvenient for the user.